The broad objective of this proposal is to delineate the role of the small intestine in zinc (ZN) homeostasis. Specifically the processes of absorption of exogenous ZN and secretion and reabsorption of endogenous ZN will be intensively investigated in complex studies in adults. Methods include multi-lumen intestinal perfusion techniques combined with ZN stable isotope methodology and model based compartmental analysis to quantitate and localize the processes of absorption of exogenous ZN and secretion and reabsorption of endogenous ZN under different experimental conditions.